Issue Communication failures occur when connecting a MicroNet ARCnet system via a MicroNet Manager Interface (MNMI) to Xenta 555/731, VisiSat, or SBO servers. Product Line Satchwell MicroNet, TAC Vista, EcoStruxure Building Operation Environment Xenta 555 or Xenta 731 communicating to a MicroNet ARCnet LAN VisiSat communicating to a MicroNet ARCnet LAN Building Operations Server communicating to a MicroNet ARCnet LAN Cause Incorrect bit switch configuration on the MicroNet MI interface. Resolution Cold Starting the MicroNet MI ⚠️ Caution: This procedure will erase all configuration data from the device’s EEPROM and restore factory defaults. Steps: Power On the Device Ensure the RUN LED flashes approximately once per second. Disconnect Communication Ports Unplug any connections to 9-pin plug 3 and 9-pin plug 4. Reset Switches Set all bit switches (S1) to the OFF position. Initiate Cold Start Toggle bit switch 8 ON, then OFF. No visible change will occur at this stage. Configure for Xenta 555 Direct Connection Set only switch 1 to ON; all others must remain OFF. Toggle bit switch 8 ON, then OFF again. Verify LEDs RUN, WINK, and MODEM LEDs should light up for ~1.5 seconds. RUN LED should resume flashing once per second. 🔍 Note: This cold-start procedure differs from that of a controller, which only requires toggling switch 8. Refer to data sheet DS10217A for detailed specifications.

Issue The Xenta Repeater features two sets of terminals labeled identically, which may cause confusion during installation. Product Line TAC Vista Environment Vista Lon Network Cause The duplicate power supply and communication terminals are internally connected. This design allows flexibility in wiring but can be misinterpreted. Resolution   Both the upper and lower terminals are electrically connected and can be used interchangeably for power and communication. These duplicate terminals are provided for convenience, allowing easier access depending on installation layout. Connect one Lon network segment to COM1 and the other to COM2. Supply the repeater with 24V power.   Wiring Examples Example 1: Traditional Bus Topology Segment 1 enters via COM1 and ends at the repeater (terminated). Segment 2 exits via COM2, beginning a new segment (also terminated). Example 2: Terminal Flexibility Same as Example 1, but demonstrates that either the upper or lower terminals can be used due to internal connectivity. Example 3: Pass-Through Configuration Segment 1 enters and exits through COM1 (not terminated, as it's not end-of-line). Segment 2 begins at COM2 and is terminated at the repeater. Additional Information For a deeper understanding of the Xenta Repeater’s role in signal restoration and conditioning on LonWorks networks, refer to: 👉 The Xenta Repeater provides signal restoration and conditioning on LON networks

Issue LON networks may experience communication issues due to excessive physical length or a high number of connected devices. The Xenta Repeater helps mitigate these issues by restoring and conditioning signals, enabling longer network spans and supporting more devices. Product Line TAC Vista Environment Vista Lon Networks Xenta Repeaters (Part # 007309120) Cause LON communication failures often stem from: Exceeding recommended cable lengths Overloading the network with too many devices Resolution The Xenta Repeater: Uses a standard Xenta 400 base Splits a LON channel into two segments Connects one segment to COM 1 terminals, and the other to COM 2 terminals 🔍 Note: A LON channel is a section of the network separated by a router. A segment is a portion of a channel divided using a repeater. 📏 Cable Length Guidelines Cable Type Max Bus Length (Doubly Terminated) Max Node-to-Node (Singly Terminated) Max Segment Length (Singly Terminated) Belden 85102 2,700 m / 8,858 ft 500 m / 1,640 ft 500 m / 1,640 ft Belden 8471 2,700 m / 8,858 ft 400 m / 1,312 ft 500 m / 1,640 ft UL Level IV 22AWG 1,400 m / 4,593 ft 400 m / 1,312 ft 500 m / 1,640 ft Siemens J-Y(st)Y 900 m / 2,953 ft 320 m / 1,050 ft 500 m / 1,640 ft TIA568A Cat.5 900 m / 2,953 ft 250 m / 820 ft 450 m / 1,476 ft 📌 Design Rules Max 128 devices per LON channel Max 64 devices per segment Up to 2 repeaters per channel (max 3 segments) If no router is used, only 64 devices allowed (single segment) Recommended: ≤ 50 devices per segment for flexibility during installation 🔄 How It Works The Xenta Repeater contains: Two internally connected LON transceivers Transient suppression circuits It: Reads LON packets from one segment Re-broadcasts them to the next segment Filters out noise, ensuring clean signal transmission Unlike simple amplifiers, it does not amplify noise, resulting in strong, noise-free communication across segments.

Issue How many alarms can be stored in a standalone programmable Xenta device? What happens to alarms when no TAC Vista system is connected? Product Line TAC Vista Environment TAC Xenta 301 TAC Xenta 302 TAC Xenta 401 TAC Xenta 281 TAC Xenta 282 TAC Xenta 283 Cause Standalone Xenta controllers have a limited internal memory capacity for storing alarms. Once this limit is reached, older alarms are overwritten. Resolution A standalone TAC Xenta controller can store up to 20 alarms. When the 21st alarm is generated, the controller uses a First-In, First-Out (FIFO) method: The oldest alarm is automatically overwritten to make space for the new one. This behavior ensures that the most recent alarms are retained, but historical alarm data may be lost if not retrieved before being overwritten.

Issue When using the economizer (outside air damper) function in the Xenta 121, specific setup considerations are required to ensure proper operation and avoid equipment damage. Environment Xenta 121-FC Xenta 121-HP Vista Workstation ZBuilder Cause The economizer function relies on a mixed air temperature sensor to prevent excessive intake of cold air, which could freeze the coil. The application logic enforces this requirement and does not allow bypassing it through software configuration. Resolution Sensor Requirement A mixed air temperature sensor is mandatory when economizer mode is enabled. If a physical sensor is not available, a ~1.8K ohm resistor can be installed in its place to satisfy the software requirement. Control Methods The economizer can operate in one of two modes: Space Temperature Control – regulates based on cooling setpoint. Mixed Air Temperature Control – regulates based on mixed air setpoint. Note: Even when using space temperature control, the mixed air temperature sensor is still required for safety lockout. Displaying Mixed Air Temperature By default, the mixed air temperature is not shown on the front end. To display it: Open ZBuilder and go to the Configuration tab. Navigate to the SNVT menu. Check the box labeled nvoGenericTemp. A tooltip will confirm this is for displaying mixed air temperature. Switch to the I/O Setup tab. The Mixed Air Temperature point will now be visible and can be assigned to the desired location.

Issue How to configure PWM (Pulse Width Modulation) output in ZBuilder for TAC Xenta 121/122 devices. Product Line TAC Vista Environment Xenta 121 Xenta 122 ZBuilder Cause Proper setup of PWM output requires understanding each parameter in the ZBuilder settings window. Resolution   Activate at % TL The PWM output control starts when Terminal Load reaches this value. Fully active at % TL The PWM output control is fully active when Terminal Load reaches this value. Min control signal % The PWM output will not send out lower percentage of full stroke. Max control signal % The PWM output output will not send out higher percentage of full stroke. Period seconds The time for one full PWM period. This period will be cyclically repeated. Pulse change if change ≥ % Applicable only for actuators giving a position directly proportional to the pulse width and not dependent of cyclic updates (PWM with US terminology). This means the output will only activate when the Terminal Load has changed more than the set value, since last activation. Normally closed The TRIAC output is connected to ground (activated) when Terminal Load is zero, and the PWM output is not active. When the PWM output activates, the TRIAC output will not be connected to ground. Normally open The TRIAC output is open, not connected to ground, when Terminal Load is zero, and the PWM output is not active. When the PWM output activates, the TRIAC output will be connected to ground.

Issue The nvoEffectSetPt is different than the nviSetPoint The nvoEffectSetPt is different than the cooling or heating setpoint (SCPTsetPnts) Product Line EcoStruxure Building Operation, TAC Vista Environment Xenta 102-AX Cause The nvoEffectSetPt is calculated according to nviSetPoint, cooling or heating setpoints (SCPTsetPnts), nviStPointOffset, and thermostat offset. Resolution The nvoEffectSetPt is a SNVT network output in Xenta 102-AX and represents the current effective setpoint that the controller is utilizing in its control loop. nvoEffectSetPt can be configured to display in two different manners: Actual and Normalized. (As defined bynciVAVselctcCntl.oP.ESS (UCPTvavSelection)) Actual nvoEffectSetPt displays the setpoint that corresponds to the currently active application mode of the controller (occupied cooling, unoccupied cooling, standby cooling, occupied heating, unoccupied heating, and standby heating). Normalized nvoEffectSetPt displays the average of the cooling and heating setpoints for the currently active occupancy mode (occupied, unoccupied, standby). NOTE: Whether nvoEffectSetPt is set to Actual or Normalized only affects how the effective setpoint is displayed and does not affect how the application operates. The 102-AX application utilizes the setpoint that corresponds to the currently active mode (occupied cooling setpoint, etc.). In addition, the thermostat adjustment of the setpoint will not appear in any SNVT in Xenta 102-AX controller. This offset is captured in the Xenta 102-AX's memory, and although it is not displayed, it is utilized into the nvoEffectSetPt calculation. Also note that the below scenarios only apply to the occupied and standby modes since the unoccupied setpoints are unaffected by nviStPointOffset, nviSetPoint or by the thermostat offset. Scenario 1: nviSetpoint is unused 1.1 Actual nvoEffectSetPt calculation: In this scenario, the nvoEffectSetPt is the sum of one(1) of the four setpoints (occupied cooling, standby cooling, occupied heating and standby heating) plus the offsets (nviStPointOffset and thermostat offset). 1.2 Normalized nvoEffectSetPt calculation: In this scenario, the nvoEffectSetPt is the average of heating and cooling setpoints ( 1/2(Occupied Cooling Setpoint + Occupied Heating Setpoint) or 1/2(Standby Cooling Setpoint + Standby Heating Setpoint) ) plus the offsets (nviStPointOffset and thermostat offset).   Scenario 2: nviSetpoint is used 2.1 Actual nvoEffectSetPt calculation: In cooling mode, the nvoEffectSetPt is the nviSetPoint plus half of the difference between cooling and heating setpoints ( 1/2(Occupied Cooling Setpoint -Occupied Heating Setpoint) or 1/2(Standby Cooling Setpoint - Standby Heating Setpoint) ),  plus the offsets (nviStPointOffset and thermostat offset). In heating mode, the nvoEffectSetPt is the nviSetPoint minus half of the difference between cooling and heating setpoints ( 1/2(Occupied Cooling Setpoint - Occupied Heating Setpoint) or 1/2(Standby Cooling Setpoint - Standby Heating Setpoint) ), then plus the offsets (nviStPointOffset and thermostat offset). 2.2 Normalized nvoEffectSetPt calculation In this scenario, whether the application is in the cooling mode or the heating mode, the nvoEffectiveSetPt is the sum of the nviSetPoint and the offsets (nviStPointOffset and thermostat Offset). Therefore, when nviSetPoint is used and nvoEffectSetPt is to Normalized, the actual heating and cooling SCPT setpoints do not matter; only the difference between them is significant. For example, setting occupied cooling and heating setpoints to be 75°F (24°C) and 65 °F (18°C) will give the same resulting nvoEffectiveSetPt as setting occupied cooling and heating to be 45°F (7°C) and 35°F (1°C).   Example Occupied Cooling = 72°F (22°C), Occupied Heating = 68°F (20°C), nviSetPoint = 75°F (24°C), assuming the nviStPointOffset and thermostat offset are zero. nvoEffectSetPt in Occupied Cooling or Heating Mode   Scenario 1.1 Scenario 1.2 Scenario 2.1 Scenario 2.2 Cooling Mode 72°F (22°C) 70°F (21°C) 77°F (25°C) 75°F (24°C) Heating Mode 68°F (20°C) 70°F (21°C) 73°F (23°C) 75°F (24°C)

Issue Which TAC Xenta I/O modules can operate as stand-alone LonWorks devices? Product Line EcoStruxure Buildings Operation, TAC Vista Environment TAC Xenta 420A TAC Xenta 421A TAC Xenta 422A TAC Xenta 450A TAC Xenta 451A TAC Xenta 452A Cause Not all TAC Xenta 400 series I/O modules are capable of functioning independently as LonWorks devices. Only specific models with an “A” suffix are designed for stand-alone operation. Resolution Only the following TAC Xenta I/O modules are capable of acting as stand-alone LonWorks devices: TAC Xenta 421A TAC Xenta 422A TAC Xenta 451A TAC Xenta 452A ⚠️ Note: TAC Xenta 400 series modules without the “A” suffix (e.g., 420, 421, 422, etc.) cannot function as stand-alone LonWorks devices. Once communication is successfully established with a compatible Xenta I/O module, the green status LED will blink on for 1 second every 10 seconds, indicating that the device is operating in stand-alone mode. Additional Information In EcoStruxure Building Operation, the LonWorks device list may display Xenta I/O modules without the “A” suffix. This can be misleading, as these non-“A” models are not capable of stand-alone operation. They are included in the list solely to allow manual addition as I/O modules to programmable Xenta controllers.

Issue How many time schedules (time objects: TSCH, TSCHI) can be added to TAC Xenta programmable devices? Product Line TAC Vista Environment TAC Xenta 301, 302, 401, 281, 282, 283 TAC Xenta 527, 511, 711, 721, 731, 701 Menta Cause The limits for time schedules are not clearly documented across all TAC Xenta controller models, leading to confusion during programming and deployment. Resolution Here are the documented limits for each controller series: TAC Xenta 7xx Series Supports up to: 50 time objects 50 week schedules 50 holiday schedules TAC Xenta 28x Series Supports: 1 TSCH block Up to 16 week/holiday charts within that block TAC Xenta 30x/40x Series No fixed limit on the number of TSCH blocks Limitation is based on available memory More schedules per block = more memory usage Optimize chart usage to conserve memory 🧠 Additional Notes When designing schedules, consider memory constraints especially for 30x/40x series. Use Menta to monitor memory usage during programming. For best practices, avoid overloading a single TSCH block with excessive charts.

Issue What is the A/D (Analog-to-Digital) resolution of the inputs and outputs on the Xenta product line? Product Line TAC Vista Environment Xenta 281/282/283 Xenta 301/302 Xenta 4xx I/O Modules Cause Project specifications often require precise information about input and output resolution to ensure compatibility and performance expectations are met. Resolution The input and output resolutions for the Xenta product line are as follows: Controller Thermistor Inputs Universal Inputs Analog Outputs Xenta 281 12-bit — 12-bit Xenta 282 12-bit — 12-bit Xenta 283 10-bit — 12-bit Xenta 301 12-bit — 12-bit Xenta 302 12-bit — 12-bit Xenta 421A / 422A — 12-bit — Xenta 451 / 452 12-bit 12-bit — Xenta 451A / 452A — 12-bit 8-bit Xenta 471 — 12-bit — Xenta 491 / 492 — — 12-bit

Issue When a TAC Xenta Operator Panel (OP) is connected to a TAC Xenta programmable controller, it displays the entire network of TAC Xenta controllers. In some cases, it's desirable to restrict the OP to only view the local controller it is directly connected to. Product line TAC Vista Environment TAC Xenta Operator Panel firmware 3.7 TAC Xenta Programmable controller 3.85 or higher Cause By default, the TAC Xenta OP scans and displays all TAC Xenta controllers on the network. This behavior may not be suitable for installations where each OP should only interact with its directly connected controller. Resolution To restrict a TAC Xenta OP to only view its local controller, follow these steps: 1. Configure the TAC Xenta Controller Edit the application in the TAC Xenta controller. Create a Public PVI block named: XENTASYSREG Set the initial value of this block to: 8 Note: If multiple OP panels are connected to different TAC Xenta controllers on the same network, you must create this PVI block in each respective controller's application code. 2. Configure the TAC Xenta Operator Panel Access the local service menu on the OP panel: Press and hold the “Escape” and “Enter” buttons simultaneously for a few seconds. Navigate to the command: 11 OP connects to Enter this menu and use the “+” or “–” buttons to select the subnet and node address of the specific TAC Xenta controller to which the OP should be locked. You can find the subnet and node address in TAC Vista Workstation: Right-click the desired TAC Xenta controller. Select Properties to view the address. After selecting the correct node, press Enter. The OP panel will restart and connect exclusively to the selected controller. Additional Notes If another OP panel (with firmware prior to version 3.70) connects to the same network, it may still access other controllers unless the lock function is also configured on that panel. Once locked, the OP panel will not allow navigation away from the assigned controller. To exit the locked controller view, press “Escape” (only possible if the lock function is not enabled or the firmware is older than 3.70).

Issue Installers occasionally use the Analog Output (AO) of Xenta controllers to operate external relays. This approach is typically adopted when additional discrete on/off control points are needed, and the AO channels are not required for proportional control. Product Line TAC Vista Environment Xenta programmable controllers Xenta 281, 282, 283, 301, 302, 401 Cause This method is often chosen to avoid the cost of upgrading to higher-capacity controllers or adding Xenta I/O expansion modules. The implementation usually involves: Connecting a 12V DC relay to the AO output. Setting the AO to 100% (10V) to energize the relay. Setting the AO to 0% (0V) to de-energize the relay. Resolution Although this use of AO for relay control is not recommended in standard designs, it can be implemented reliably if the following considerations are addressed: Relay Selection: Ensure the relay is compatible with the AO voltage and current characteristics. Installation Practices: Proper wiring, isolation, and protection should be applied to prevent damage or erratic behavior. Controller Configuration: Confirm that the AO channel is correctly programmed to deliver the required voltage levels. For detailed guidance, refer to the document: 📄 Xenta Analog Output WP-001.040804.pdf

Issue How to enable the Service Menu on a TAC Xenta controller via the Operator Panel (OP). Product Line TAC Vista Environment TAC Xenta OP TAC Menta Cause The Service Menu is not enabled by default. To access advanced configuration options such as viewing system program version, device name, network address, and I/O module settings, the Service Menu must be explicitly enabled during OP tree configuration. Resolution To enable the Service Menu on the TAC Xenta controller: Open the OP Configuration Tool. Edit the OP Tree: Navigate to Formats > Settings. Locate and select the “Use Service Menu” option. Save and generate the updated OP tree. Upload the new configuration to the OP. Once enabled, the Operator Panel will allow you to: View the system program version, device name, and network address. Configure I/O modules. Restart the device directly from the OP.

Issue Which template should be used for the following TAC Xenta controllers? TAC Xenta 102-B TAC Xenta 102-VF TAC Xenta 102-EF Product Line TAC Vista Environment TAC Xenta 102-B TAC Xenta 102-VF TAC Xenta 102-EF Cause All three controller models—102-B, 102-VF, and 102-EF—share the same configuration and operational characteristics, allowing them to use a common template. Resolution Use the TAC Xenta 102 template in TAC Vista for all three models: 102-B 102-VF 102-EF This ensures consistent setup and functionality across these devices.

Issue Certain Xenta controllers and I/O modules support 10k thermistor temperature inputs. A common question arises regarding the specific type of 10k thermistor that is compatible—specifically, whether it should be Type 2 or Type 3. Product Line EcoStruxure Building Operation, TAC Vista Environment Xenta 102-AX Xenta 420A, Xenta 450A Cause The Xenta 102-AX has always utilized 10k thermistors. More recently, some I/O modules and programmable controllers within the Xenta family (e.g., Xenta 420A and 450A) have also added support for 10k thermistor inputs. However, confusion often arises due to terminology differences. The terms “10k Type 2” and “10k Type 3” are specific to the Continuum product line and are not applicable to Xenta controllers. Resolution The 10k thermistors compatible with Xenta 42XA and 45XA I/O modules are the same as those used in the I/NET product line. These thermistors follow the Vishay Dale Curve #1 specification. For accurate configuration and calibration, refer to the Resistance vs. Temperature Conversion Tables provided in the linked PDF document below: 📄 Resistance vs Temperature Conversion – Vishay Dale.pdf

Issue Can TAC Xenta 401 and TAC Xenta 300 HW1 be upgraded to the latest system version? Product Line EcoStruxure Building Operation, TAC Vista Environment TAC Xenta 401 TAC Xenta 301 TAC Xenta 302 Cause Upgrading to the latest system version is recommended to benefit from the most recent product fixes, performance improvements, and feature enhancements. Resolution   TAC Xenta 300 and Xenta 401 units can be upgraded to any system version. However, HW1 versions are not compatible with EcoStruxure Building Operation. All hardware versions, including HW1, are supported in the TAC Vista Classic system.  

Issue Guidance is needed for configuring the Remote Alarm Manager (RAM), including understanding its components, available documentation, and script customization. Product Line Satchwell BAS & Sigma, Satchwell MicroNet, TAC Vista Environment Remote Alarm Manager Cause RAM configuration involves multiple components such as: Configuration Controller Monitoring Scripts Output Interfaces Users may encounter challenges due to the complexity of these elements or lack of familiarity with scripting in RAM. Resolution To assist with setup and customization, three key guides are available: Operator’s Manual Basic usage and interface overview Ideal for day-to-day operations Engineer’s Manual More comprehensive than the Operator’s Manual Covers advanced configuration and troubleshooting Script Editor’s Guide Details on customizing and adapting scripts Useful for tailoring RAM behavior to specific site needs 📁 Location of Scripts: Scripts used by RAM are located in: C:\Satchwell\Binary\Remote Alarm Manager File extension: .scr Best practice: Copy and rename scripts before editing to preserve originals.

Issue Building Management System (BMS) equipment may malfunction due to electromagnetic interference (EMI) from nearby electrical devices. Diagnosing and resolving such issues can be complex and costly, making preventive installation practices essential. Product Line Andover Continuum, EcoStruxure Building Operation, Field Devices, Satchwell MicroNet, Satchwell Sigma, TAC IA Series, TAC Vista Environment All electrical equipment Cause Improper installation can lead to the generation or exposure to high- and low-frequency EMI, which may disrupt system performance or cause equipment failure. Resolution To ensure reliable operation and minimize EMI-related issues, follow these key EMC installation practices: Key EMC Practices Follow Manufacturer Recommendations Always adhere to the installation guidelines provided by equipment manufacturers, as they are tailored to the specific EMC requirements of each product. Proper Cable Routing Separate power and signal cables. Avoid parallel runs near high-interference sources (e.g., motors, transformers). Shielding Use shielded cables for sensitive signals. Ground shields correctly—typically at one end to prevent ground loops. Grounding and Bonding Establish a low-impedance ground path. Bond all equipment to a common ground reference. Surge Protection Install surge protection on power and communication lines. Protect against lightning and switching transients. Filtering Use EMI filters on power inputs. Apply ferrite beads or chokes on signal lines where needed. Physical Separation Maintain spacing between high-voltage and low-voltage components. Isolate noisy equipment from sensitive electronics. Enclosure Design Use metal enclosures for shielding. Ensure proper sealing and grounding of enclosure panels. Installation Environment Avoid placing equipment near strong EMI sources (e.g., radio transmitters, welding equipment). Maintain clean, dry conditions to prevent corrosion and poor connections. Compliance Testing Verify installations against relevant EMC standards (e.g., IEC, EN). Conduct site surveys if persistent issues arise. Reference Document: Practical Installation Guidelines for Electromagnetic Compatibility

Issue When attempting to directly download Menta code from a Xenta 280 or Xenta 300 controller to a Xenta 401 or Xenta 401:B controller, users may encounter the error: PARSER IO ERROR 13 Environment TAC Menta TAC Xenta 280 / Xenta 300 TAC Xenta 401 / Xenta 401:B Cause The Xenta 280 and 300 controllers have physical I/O points (e.g., M0-X1, M0-U2) directly on the device. These are referenced in the Menta application as M0 terminals. However, the Xenta 401 series does not have onboard physical I/O. When code containing M0 references is copied into a Xenta 401 Menta application, these I/O points become invalid. Since the points were copied manually (not created within the application or imported from a library), simulation mode does not detect the terminal mismatch. This leads to failed downloads and the PARSER IO ERROR 13 during direct serial communication. Resolution To resolve this issue: Open the Menta application for the Xenta 401. Navigate to Options > IO Configuration Table. Sort the table by the "Bound to" column to identify physical I/O references. Locate all points referencing M0 terminals. Reassign these points to valid physical I/O terminals appropriate for the Xenta 401 application.

Issue How can the TAC Xenta OP be used with a TAC Xenta 100-series controller? How does the OP identify which TAC Xenta 100 controller it's communicating with? Which OP mode should be used? Product Line TAC Vista Environment TAC Xenta OP TAC Xenta 101 TAC Xenta 102 TAC Xenta 121 TAC Xenta 122 Cause   The TAC Xenta OP panel allows access to input and output signals from a TAC Xenta 100-series controller. Identification of the specific controller is achieved via a Service Pin message. If connected directly to a TAC Xenta 100-series controller or a STR100-series device attached to it, the controller automatically sends a Service Pin message. If connected elsewhere on the network, you may need to manually press the Service Pin on the desired controller. For troubleshooting connectivity issues, refer to: “No Answer” on an OP when connecting to a Xenta 280/300/400 Resolution 1. Configure the TAC Xenta OP Plug in the TAC Xenta OP. Hold Back and Enter for 3 seconds to access the OP Service Menu. Scroll to Option 10: OP Mode. Set “Xenta 100” to ON using the + key. Press Enter. Set “Mode” to TAC using the + key. Press Enter twice to restart the OP. 2. Connect to a TAC Xenta 100-series Device Plug the OP into the OP jack on the TAC Xenta 100 controller or a connected STR100 device. When prompted “Press to access Xenta 100”, press Enter. At “Connecting to Xenta 100…”, wait or press the Service Pin on the controller. Press Down to proceed. 3. View and Modify Network Variables At the NV Index? prompt, use +/- to select the desired network variable index. Press Enter to view the signal. If the value is an input: Use +/- to modify the value. Press Enter to accept. If the signal is a bit-based application option: Press Enter to navigate between bits. Use + to change the bit value. Press Enter to confirm.